# US 12,009,499 B2 · Electrochemical conversion of halogenated compounds and associated systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,009,499 B2 - Document ID: US12009499B2 - Status: Granted - Kind: B2 - Application number: 17/969,486 - Filed: 2022-10-19 - Published: 2023-02-16 - Granted: 2024-06-11 - Earliest claimed: 2016-10-03 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: Betar Gallant; Yuanda Li; Aliza Khurram; Mingfu He - Web page: https://patentgrep.com/patent/US12009499B2 ## CPC - H01M 12/06: with one metallic and one gaseous electrode - H01M 4/382: {Lithium (H01M4/405 takes precedence)} - H01M 4/582: {Halogenides} - H01M 4/8605: {Porous electrodes} - H01M 4/40: Alloys based on alkali metals - H01M 4/46: Alloys based on magnesium or aluminium - H01M 6/14: Cells with non-aqueous electrolyte - H01M 12/04: composed of a half-cell of the fuel-cell type and of a half-cell of the primary-cell type - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Methods and systems for the electrochemical conversion of halogenated compounds are provided. In some embodiments, a method comprises converting a halogenated compound (e.g., fluorinated gas) to relatively non-hazardous products via one or more electrochemical reactions. The electrochemical reaction(s) may occur under relatively mild conditions (e.g., low temperature) and/or without the aid of a catalyst. In some embodiments, the electrochemical reaction may produce a relatively large amount of energy. In some such cases, systems, described herein, may be designed to facilitate the conversion of the halogenated compound (e.g., SF6, NF3) while harnessing (e.g., storing, converting) the energy associated with the electrochemical reaction. System and methods described herein may be used in a wide variety of applications, including waste management (e.g., environmental remediation, greenhouse gas mitigation), energy recovery (e.g., industrial energy recovery), and primary batteries (e.g., metal-gas batteries). ## Claims ### Claim 1 A method, comprising: in a sealed electrochemical cell, reacting a halogenated compound with a metal to form a metal halide, wherein the halogenated compound is a gas at standard temperature and pressure and the metal has a standard reduction potential of less than or equal to about −1.4 V vs. a standard hydrogen electrode. ### Claim 2 (depends on 1) The method of claim 1, comprising reacting the halogenated compound with the metal in an electrolyte to form the metal halide. ### Claim 3 (depends on 2) The method of claim 2, wherein the electrolyte comprises a non-aqueous solvent. ### Claim 4 (depends on 2) The method of claim 2, wherein the electrolyte comprises an organic solvent. ### Claim 5 (depends on 1) The method of claim 1, wherein the reacting step occurs at a temperature of less than or equal to about 60° C. ### Claim 6 (depends on 1) The method of claim 1, wherein the reacting step occurs at a pressure of greater than or equal to about 1 atm. ### Claim 7 (depends on 1) The method of claim 1, wherein the reacting step occurs at a cathode. ### Claim 8 (depends on 7) The method of claim 7, wherein the cathode comprises carbon, a noble metal, a transition metal, a metal oxide, or a metal fluoride. ### Claim 9 (depends on 7) The method of claim 7, wherein the cathode comprises carbon nanotubes, graphene, and/or carbon nanofibers. ### Claim 10 (depends on 1) The method of claim 1, wherein the halogenated compound is reduced during the reacting step. ### Claim 11 (depends on 1) The method of claim 1, further comprising forming a second reaction product as a result of the reacting step. ### Claim 12 (depends on 1) The method of claim 1, wherein the metal is selected from the group consisting of alkali metals and alkaline earth metals. ### Claim 13 (depends on 1) The method of claim 1, wherein the metal is lithium or sodium. ### Claim 14 (depends on 1) The method of claim 1, wherein the electrochemical cell is a galvanic cell. ### Claim 15 (depends on 1) The method of claim 1, wherein the halogenated compound is a fluorinated compound. ### Claim 16 (depends on 1) The method of claim 1, wherein the halogenated compound is selected from the group consisting of sulfur hexafluoride, nitrogen trifluoride, and perfluorinated fluorocarbons. ### Claim 17 (depends on 1) The method of claim 1, wherein the metal halide is a metal fluoride. ### Claim 18 (depends on 1) The method of claim 1, wherein the sealed electrochemical cell comprises an anode, and wherein the anode comprises a metal selected from the group consisting of alkali metals and alkaline earth metals. ### Claim 19 (depends on 18) The method of claim 18, wherein the anode comprises lithium or sodium. ### Claim 20 (depends on 1) The method of claim 1, further comprising maintaining a concentration of the gas in a headspace of the sealed electrochemical cell that allows the gas to be transported from the headspace to an electrolyte of the sealed electrochemical cell prior to, during, and/or after use of the sealed electrochemical cell. ### Claim 21 A method, comprising: at an electrified interface of a cathode, electrochemically reacting a halogenated compound with a metal ion to form a metal halide, wherein the halogenated compound is a gas at standard temperature and pressure and the metal ion has a standard reduction potential of less than or equal to about −1.4 V vs. a standard hydrogen electrode. ### Claim 22 (depends on 21) The method of claim 21, wherein the metal ion is a lithium cation and/or a sodium cation. ### Claim 23 (depends on 21) The method of claim 21, wherein the cathode comprises carbon, a noble metal, a transition metal, a metal oxide, or a metal fluoride. ### Claim 24 (depends on 21) The method of claim 21, wherein the electrified interface of the cathode is an electrified interface between the cathode and an electrolyte. ### Claim 25 (depends on 24) The method of claim 24, wherein the halogenated compound is dissolved in the electrolyte.